The invention relates to a plate link chain in the form of a conveyor chain, especially for platform or apron conveyors, bucket conveyors, or similar conveying means, comprised of at least two chain strands that are disposed parallel to one another and are comprised of a sequence of inner plate members and outer plate members, whereby the inner plate members are provided with openings for receiving at least one sleeve for connecting the inner plate members of the oppositely disposed chain strands, and the outer plate members are provided with openings that are lined with the openings of the inner plate members in order to receive a link pin that extends through the sleeve and is fixed on the outer plate members, and at least the inner plate members and/or the outer plate members that form one chain strand are provided with angle brackets for the mounting of further components of the conveying means.
A plate link chain having the aforementioned features is described in DIN Standard 8167 as well as in DIN Standard 8175. Such plate link chains have the problem that the maximum tensile load of the chain that can be taken up is determined by the weakest chain element, i.e. the inner plate member, the outer plate member, the sleeve or the link pin. In this connection, experience has shown that with the state of the art plate link chains, the inner plate member having the bore for receiving the chain sleeve, which bore weakens the cross-sectional area of the inner plate member, represents the weak point of a state of the art plate link chain. To the extent within the scope of the known manufacturing processes the plates are manufactured from rolled metal plate by stamping, shearing or laser cutting, out of economical reasons these manufacturing processes permit only a specific plate thickness, as a result of which the maximum permissible tensile load of the plate link chain is also limited. If greater tensile loads of the chain are necessary, disproportionately process-intensive, and hence expensive, forged chains are used.
To the extent that with the plate link chain described in GB 193 547 components such as angle brackets that are to be attached are placed upon additionally arranged bolts, the problem presented with regard to the configuration of the inner plate members that carry the sleeves is not eliminated thereby.
Known from GB 2 135 018 A, U.S. Pat. No. 1,694,746 and JP60-191903 are roller chains with which a shaft that carries the respective roller is likewise carried in the inner plate members and outer plate members of the chain, which to this extent are appropriately embodied the same; there thus does not result a differing loading of the inner of the members and outer plate members.
It is therefore an object of the invention, with a plate link chain having the aforementioned features, to provide a uniform loading of all elements of the chain, and possibly to increase the permissible tensile load of the chain.